A magnetic resonance imaging (MRI) device, a magnetic resonance spectroscopy (MRS) device, etc. are well known as a magnetic resonance system using nuclear magnetic resonance (NMR) phenomena.
An MRI device captures images of cross-sections of a human body by using NMR phenomena. Since atomic nuclei such as hydrogen (1H), phosphorous (31P), sodium (23Na), and carbon isotopes (13C) existing in a human body each have a unique rotating field constant due to the NMR phenomena, a high frequency signal is applied to magnetization vectors of the atomic nuclei arranged in a direction of a main magnetic field by using a RF coil, and the images of the cross-sections of the human body may be obtained as the RF coil receives a magnetic resonance signal generated when the magnetization vectors are rearranged on a vertical plane due to frequency resonance.
The RF coil includes a RF antenna that transmits high frequency signal and receives a magnetic resonance signal to resonate the magnetization vectors. The resonance of the magnetization vectors by using one RF coil (the RF antenna) (i.e., a RF transmission mode) and receiving the magnetic resonance signal (i.e., a RF receiving mode) may be simultaneously performed. Alternatively, a RF coil only for the RF transmission mode and a RF coil only for the RF receiving mode are separately used to separately perform the RF transmission mode and the RF receiving mode. A coil that performs both the RF transmission mode and the RF receiving mode is referred to as a transmit/receive (Tx/Rx) coil. A Tx only coil is referred to as a transmission coil, and a Rx only coil is referred to as a receiving coil. RF transmission coils are mostly installed within a main magnet and are in a cylindrical form or a birdcage form above a cylindrical frame which has a sufficient size to fit a human body therein. On the contrary, RF receiving coils may be located close to the human body and be in various forms, depending on shapes of body parts.